Organic light emitting diodes OLEDs have been increasingly applied in a high performance display field as a current-type light-emitting device due to its characteristics of self-luminance, rapid response, wide view angle, possibility of being produced on a flexible substrate and so on. OLED display devices can be divided into passive matrix driving OLED PMOLED and active matrix driving OLED AMOLED according to their different driving manners. It can be expected that the AMOLEDs will replace liquid crystal displays as a next generation of new flat-panel display due to its advantages of low manufacturing cost, high response rapid, power saving, possibility of being applied into DC driving of portable devices, wide range of operational temperature and so on. Therefore, AMOLED display panels have attracted a lot of attentions.
Generally, an AMOLED panel is driven by gate driving signals having a plurality of pulses. In addition, in a LCD panel, in order to ensure fully charging, gate driving signals having a plurality of pulses are also required for driving. However, it is impossible to generate a gate driving signal having a plurality of pulses by a single shift register currently.